They are the most famous words in the history of space exploration, but the origins of Neil Armstrong's pithy "One Small Step" speech may not be what they seem.

The first man on the Moon maintained until his death last August that his choice of words had been spontaneous, conceived shortly before setting foot on the lunar surface; but a recent interview with his brother suggests that Armstrong's iconic two-liner was actually planned several months in advance.

"He says, 'What do you think about that?' I said 'fabulous.' He said 'I thought you might like that, but I wanted you to read it,'" Dean Armstrong is quoted as saying in a Telegraph report on the [recently aired BBC documentary], titled "Neil Armstrong: First Man on the Moon."

Nobody wants to remember Armstrong as a liar; but to that end, this new information comes with something of a silver lining. While his brother's story suggests that history's first moonwalker may have fibbed about the birth of the phrase, the revelation lends credence to another of Armstrong's long-standing claims: that, contrary to NASA's audio recordings, he did, in fact, say "that's one small step for A man," as opposed to the contextually inappropriate "that's one small step for man":

After the flight, Armstrong insisted that he intended to say "a man." Some experts say that the "a" was dropped because of a glitch in the radio signal, but most assume that Armstrong just left out the word... If he did leave out the word, it's a natural slip to make: Dean Armstrong omitted the "a" himself the first time he quoted the phrase, and had to correct himself a moment later. "It was 'that is one small step for A man,'" he said.

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